1. Field of the Invention
The present invention relates to a method and a device for displacing and storing brake fluid for a hydraulic brake system of a vehicle.
2. Description of Related Art
In a hydraulic brake system of a vehicle, a brake pedal is mostly actuated by the driver and, with the optional assistance of a brake booster, mechanically displaces a piston in a master brake cylinder, at whose outlets a hydraulic unit is connected. In this manner, brake fluid is introduced into the hydraulic unit (e.g., ESP or ABS) and directed to the wheel brake cylinders. There, the introduced volume increases the brake pressure and causes braking action by pressing the brake pads onto the brake disks.
In modern brake systems, brake calipers are often provided with an increased gap between brake pads and brake disks to reduce the friction of the brake and thereby minimize fuel consumption. This gap is set in a purely mechanical manner and is a function of, inter alia, the time of brakeless travel. For this reason, the size of the gap is not always the same. In the case of manipulating the brake pedal, this results in, inter alia, a pedal play up to the point of closing the gap, which is a function of the driving situation; and therefore, this results in a non-reproducible relationship between pedal travel and total braking torque. The pedal characteristic may be different from braking instance to braking instance.
In addition, such a gap reduces the dynamic response of a braking action, since in the event of manipulating the brake pedal, any existing gap causes the braking action to still not occur immediately.